Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.1.7 (acetylcholinesterase)
 28,390 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Cholinesterasic activity of umbilical cord (tissue), completely bloodless, is exclusively due to pseudocholinesterase. Cholinesterase is more active in placenta than in cord; it is an acetylcholinesterase at 80 per cent. Both forms coexist, about equally, in amniotic membrane. A considerable arylesterasic activity is proved in cord, placenta and membrane, the greatest activity being in placenta. Comparing the greater activity in maternal plasma and cord blood's plasma to the very weak activity in amniotic fluid, it is possible to think that cork, membrane, placenta and also amniotic fluid pseudocholinesterase and arylesterase, come from plasma. On the contrary, placental acetylcholinesterase seems original and probably is the source of this enzyme activity in amniotic fluid.
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PMID:[Cholinesterases and arylesterase in the umbilical cord, the placenta, and the amniotic membrane, in the female at term]. 14 88

A chiral phosphotriester, methyl n-butyl p-nitrophenyl phosphate was used to determine the stereospecificity of hydrolysis catalysed by serum phosphotriesterases (aryl-ester hydrolases, EC 3.1.1.2) from horse, ox and rabbit. Each enzyme hydrolysed the (-)-enantiomer more quickly. The same phosphate was used to inhibit acetycholinesterase (acetycholine hydrolase, EC 3.1.1.7) from ox, rabbit and electric eel, and in each case, the (+)-enantiomer caused more rapid inhibition. Serum phosphotriesterase did not catalyse the dephosphorylation of dialkyphosphoryl-acetylcholinesterase or dialkylphosphoryl-carboxylesterase. Levels of serum phosphotriesterase in rabbits which received sub-lethal injections of the phosphotriester remained unchanged after one or several injections. In the same rabbits, the levels of blood acetylcholinesterase fell sharply following injections, but normal values were regained in 2-8 days. Serum phosphotriesterases seem incapable either of preventing acute phosphotriester poisoning or of regenerating active enzyme from phosphorylated acetylcholinesterase. However, phosphotriesterases would act in cases of chronic exposure by catalysing the hydrolysis of such organophosphate poisons as remain in the blood.
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PMID:Organophosphate inhibitors. The stereospecificity of hydrolysis of methyl n-butyl p-nitrophenyl phosphate by serum phosphotriesterases (EC 3.1.1.2) and by acetylcholinesterases (EC 3.1.1.7). 19 Oct 80

Incubation of the sera of 799 nonrelated persons with paraoxon led to varying degrees of inhibition of the serum cholinesterase (EC 3.1.1.8) with residual activity between 0% and 67.4% of the initial activity. This is the result of a differing paraoxonase (EC 3.1.1.2) activity. The residual activities show a trimodal distribution. The results of studies of 99 families with children show that an autosomal dominant herdity factor is most likely. Consideration of the constellations of the activity values within the families can thus yield a stochastic external criterion. This, together with the shape of the distribution of the individual values, gives good statistical estimates for the distributions and frequencies of the three groups obtained by an iteration technique. Tests of association that take account of group membership show that residual activity does not depend on the blood groups A, B, O, and Rh, or on age. A conclusive argument for our assumption of three activity groups is that the resulting group frequencies are consistent with the Hardy-Weinberg rule.
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PMID:On the genetics of the human serum paraoxonase (EC 3.1.1.2). 22 68

1. Disc electrophoresis was used to determine the esterase isoenzymes present in adults of the strigeoid trematode Alaria marcianae (La Rue, 1917). 2. Eight esterase bands were found with alpha-naphthyl acetate as the substrate and Fast Blue RR as the dye. 3. From results obtained with inhibitors, four different types of esterases were tentatively identified; cholinesterase (one band), ali-esterase or B-type (one band), arylesterase or A-type (2 bands) and acetylesterase or C-type (4 bands).
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PMID:Electrophoretic separation of esterases of Alaria marcianae (La Rue, 1917) (Trematoda). 31 43

1. The nonspecific esterases of the mosquito, Culex tarsalis, were examined through conventional and isoelectric focusing acrylamide gel electrophoresis. 2. Conventional acrylamide gel electrophoresis resolved five components. These were characterized as: three carboxylesterases, one acetylcholinesterase and one acetylesterase. 3. Isoelectric focusing resolved 18 components. These were characterized as: 14 carboxylesterases, two acetylcholinesterases, one acetylesterase and one arylesterase. 4. The reproducibility and reliability of isoelectric focusing is discussed and compared to conventional acrylamide gel electrophoresis for the examination of multi-component isozyme systems such as non-specific esterases.
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PMID:Electrophoretic characterization of the nonspecific esterases of the mosquito, Culex tarsalis: conventional and isoelectric focused acrylamide gels. 31 77

Bovine erythrocyte acetylcholinesterase and human plasma cholinesterase are irreversibly inhibited by diethylmesoxalate hydrate, the inhibition potency being comparable to that of certian insecticidal organophosphates and carbamates. Insect cholinesterases, however, appear to be much less affected by diethylmesoxalate hydrate. The compound was also found to inhibit the hydrolysis of paraoxon by rabbit plasma A-esterase, but in a reversible mode.
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PMID:Diethylmesoxalate hydrate, a new irreversible inhibitor of cholinesterases. 44 48

The effect of tricresylphosphate (TCP) was studied in vitro and in vivo on the rat liver and brain enzymes acetylcholinesterase (ACC), butyrylcholinesterase (CHE), arylesterase (ARE), aliesterase (ALI), and the microsomal nicotinamide-adenine dinucleotide phosphate oxidase (NADPH2-oxidase) system. The results show that, in the male rat, TCP given intraperitoneally induces an increase in liver microsomal ARE AND NADPH2-oxidase and a decrease in ALI and cholinesterase; no activation of ARE and NADPH2-oxidase is observed in female rats.
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PMID:Effects of tricresylphosphate on esterase activity of rat serum and tissues. 46 77

Human erythrocytes contain a butyrylesterase which, judging from the ease with which it can be solubilized, is present in the cytoplasm of these cells. This enzyme has been isolated and a number of its properties characterized. The purified enzyme hydrolyzed butyryl esters with both a lower Km and higher V than is seen with esters containing longer or shorter acyl groups. It has a molecular weight of 320 000 and an isoelectric point of 4.1. This low isoelectric point is apparently a result of the relatively high content of glutamic and aspartic acids. The stability of the isolated butyrylesterase has been examined under a number of different conditions. The enzyme is inhibited by low concentrations of Hg2+, Cd2+, Zn2+ and the organophosphorus compound Mipafox, but is insensitive to eserine. The properties of this butyrylesterase, including its ability to hydrolyze thiocholine esters at a relatively rapid rate (albeit with a high Km), are a mixture of those expected for an arylesterase and a cholinesterase.
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PMID:Isolation and characterization of a butyrylesterase from human erythrocytes. 48 6

A study is presented on the activity of cholinesterase (substrate acetylcholine) and of arylesterase (substrate phenylactate) in proteinuria, classified according to the results of electrophoresis of glomerular and tubular proteinuria. Comparison is made with the corresponding serum. The urine is concentrated by dialysis on polyethylene-glycol to 60 g protein per 1000 before determination of the activities. In the presence of equal quantities of protein, cholinesterase is slightly more active in glomerular than in tubular proteinuria. In selective glomerular proteinuria, cholinesterase and arylesterase are less active than in cases with little or no selectivity. Comparison with serum, in each individual case, indicates that the ratio of activity in concentrated urine to that in serum, is higher for cholinesterase and arylesterase in tubular than in glomerular cases, whereas the reverse is true in urine at its natural concentration, on account of the lower degree of proteinuria in tubular cases. The ratio of cholinesterase to arylesterase activity in concentrated urine and serum is determined. Since cholinesterase activity is greatly increased in glomerular cases (nephrosis) this ratio is on average markedly higher in glomerular proteinuria than in serum, whereas it is similar in urine and serum of tubular cases. These results, seen in the light of the molecular weights of the enzymes, are difficult to interpret with certainty, especially as regards tubular proteinuria.
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PMID:[Cholinesterase, arylesterase and proteinuria. A clinical trial in glomerular and tubular proteinuria (author's transl)]. 71 86

In blood serum of patients with lymphogranulomatose, as compared with healthy persons, a decrease in activity of one of the arylesterase fractions was observed. In lymphogranulomatous process content of this fraction and content of cholinesterase were decreased in liver tissue more distinctly than in the blood. At the same time the arylesterase activity was increased; the enzyme was found only in trace amount in normal liver tissue. The impairments in content of lactate dehydrogenase isozymes were less distinct. In lymphogranulomatose the activity of alkaline phosphatase was increased, especially in cases accompanied by impairment of liver tissue.
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PMID:[The study of isoenzymes of esterase, lactate dehydrogenase and alkaline phosphatase from blood serum in lymphogranulomatous process of liver tissue]. 121 67


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